diff options
| author | Ian Rogers <irogers@google.com> | 2023-10-12 20:56:45 +0300 |
|---|---|---|
| committer | Namhyung Kim <namhyung@kernel.org> | 2023-10-17 22:40:50 +0300 |
| commit | 0197da7affab502cd6e25da616ad038b169a7a77 (patch) | |
| tree | 4d6ee74bb61b24c72399d2e533de338a9fc64f37 /tools/perf/util/pmu.h | |
| parent | f20c15d13f017d4b46523990a0f3ba42025391a6 (diff) | |
| download | linux-0197da7affab502cd6e25da616ad038b169a7a77.tar.xz | |
perf pmu: Lazily compute default config
The default config is computed during creation of the PMU and may do
things like scanning sysfs, when the PMU may just be used as part of
scanning. Change default_config to perf_event_attr_init_default, a
callback that is used when a default config needs initializing. This
avoids holding onto the memory for a perf_event_attr and copying.
On a tigerlake laptop running the pmu-scan benchmark:
Before:
Running 'internals/pmu-scan' benchmark:
Computing performance of sysfs PMU event scan for 100 times
Average core PMU scanning took: 28.780 usec (+- 0.503 usec)
Average PMU scanning took: 283.480 usec (+- 18.471 usec)
Number of openat syscalls: 30,227
After:
Running 'internals/pmu-scan' benchmark:
Computing performance of sysfs PMU event scan for 100 times
Average core PMU scanning took: 27.880 usec (+- 0.169 usec)
Average PMU scanning took: 245.260 usec (+- 15.758 usec)
Number of openat syscalls: 28,914
Over 3 runs it is a nearly 12% reduction in execution time and a 4.3%
of openat calls.
Signed-off-by: Ian Rogers <irogers@google.com>
Reviewed-by: Adrian Hunter <adrian.hunter@intel.com>
Cc: Ravi Bangoria <ravi.bangoria@amd.com>
Cc: James Clark <james.clark@arm.com>
Cc: Suzuki K Poulose <suzuki.poulose@arm.com>
Cc: Yang Jihong <yangjihong1@huawei.com>
Cc: Will Deacon <will@kernel.org>
Cc: Leo Yan <leo.yan@linaro.org>
Cc: Mike Leach <mike.leach@linaro.org>
Cc: Jing Zhang <renyu.zj@linux.alibaba.com>
Cc: Kajol Jain <kjain@linux.ibm.com>
Cc: Thomas Richter <tmricht@linux.ibm.com>
Cc: Kan Liang <kan.liang@linux.intel.com>
Cc: John Garry <john.g.garry@oracle.com>
Cc: linux-arm-kernel@lists.infradead.org
Cc: coresight@lists.linaro.org
Link: https://lore.kernel.org/r/20231012175645.1849503-8-irogers@google.com
Signed-off-by: Namhyung Kim <namhyung@kernel.org>
Diffstat (limited to 'tools/perf/util/pmu.h')
| -rw-r--r-- | tools/perf/util/pmu.h | 7 |
1 files changed, 4 insertions, 3 deletions
diff --git a/tools/perf/util/pmu.h b/tools/perf/util/pmu.h index 5a05131aa4ce..d2895d415f08 100644 --- a/tools/perf/util/pmu.h +++ b/tools/perf/util/pmu.h @@ -92,10 +92,11 @@ struct perf_pmu { */ int max_precise; /** - * @default_config: Optional default perf_event_attr determined in - * architecture specific code. + * @perf_event_attr_init_default: Optional function to default + * initialize PMU specific parts of the perf_event_attr. */ - struct perf_event_attr *default_config; + void (*perf_event_attr_init_default)(const struct perf_pmu *pmu, + struct perf_event_attr *attr); /** * @cpus: Empty or the contents of either of: * <sysfs>/bus/event_source/devices/<name>/cpumask. |